Mineral-wool mats are being used to a growing extent as heat-insulating and soundproofing elements, as well as for fire protection.
In the manufacture of mineral-wool mats, the raw materials which are stored in bins are fed via a weighing and conveying system to a melting furnace, in which they are melted at elevated temperatures. The fluid stream of material flows into a spinner which produces thin mineral fibers, said fibers being deposited, after a resin binder has been added, in the form of a continuous resin-impregnated mat in a collection chamber. During spinning and prior to the depositing process, there is a continuous release of mineral waste products having temperatures near the melting point and being in the form of beads of material from the melting process, slag, loose bits of fibers and such like. In an adjoining curing chamber, the raw mat is obtained in the required final thickness. This raw mat is inexact in width and therefore has to be trimmed at the sides. In further steps, it thus passes through a trimming station, in which it is trimmed, and then through a sizing station, in which it is cut to the desired length. An inspection and check for defects is the last step of the manufacturing process.
A shortcoming of this known manufacturing process is the unduly high proportion of waste products in the form of beads of material from the melting process, slag, loose bits of fibers obtained immediately downstream of the spinner, as well as of resin-impregnated pieces cut off the edges--some of which pieces have not been cured--which are obtained at the trimming station and entire scrap slabs from the inspection and check for defects.
These waste products have, so far practically without exception, been delivered to a suitable dump, as they cannot be utilized in the form in which they are obtained.
The purpose behind the invention is to make use of the waste products.
It is therefore an object of the invention to further develop the known process for manufacturing mineral-wool mats in such a manner that practical use can be made of the waste products.
It is a further object of the invention to devise equipment for performing the process according to the invention.